1.
    if ((n > 32,767) or (n < -32,767)) { n.selectUseType = long; }
2.
    if (there are large arrays or many structures) { n.selectUseType = short; }
3.
    if ((well-defined overflow characteristics are important ) or
        (not negative values) or
        (manipulating bits or bytes and not want to meet sign-extension problems))
    {
        n.selectUseType = unsigned n.selectUseType;
    }
4.
    assert(not use unsigned char replace integer type);
5.   
    assert(sizeof(char) <= sizeof(short) <= sizeof(int) <= sizeof(long) <= sizeof(long long));
6.
    if (Under ANSI C)
    {
       nTypeMin = <limits.h>.maximum;
       nTypeMax = <limits.h>.minimum;
    }
7.
    if (want to define an exact size object)
    {
        n.selectUseType = typedef userDefineType;   
    }